Concept explainers
In March 2011, the Fukushima Daiichi nuclear power plant in Japan experienced a meltdown; consequently, radioactive materials were released into the environment. On the International Nuclear Event Scale (INES) running from 0 (indicating an abnormal situation with no safety consequences) to 7 (indicating an accident causing widespread contamination with serious health and environmental effects), the incident received a rating of 7. The only other recorded level 7 incident is the Chernobyl (Ukraine) meltdown in 1986.
One of the radioactive materials released during the Fukushima disaster was cesium-137; cesium-137 has a half-life of 30.2 years. How long will it take for this material to lose the following amount of its radioactivity?
a. 90%
b. 99%
c. 99.9%
Want to see the full answer?
Check out a sample textbook solutionChapter 10 Solutions
MATHEMATICS A PRACTICAL ODYSSEY W/ACCESS
- A company studied the number of lost-time accidents occurring at its Brownsville, Texas, plant. Historical records show that 10% of the employees suffered lost-time accidents last year. Management believes that a special safety program will reduce such accidents to 7% during the current year. In addition, it estimates that 15% of employees who had lost-time accidents last year will experience a lost-time accident during the current year. a. What percentage of the employees will experience lost-time accidents in both years (to 2 decimals)? % b. What percentage of the employees will suffer at least one lost-time accident over the two-year period (to 2 decimals)? Check My Work (2 remaining) %arrow_forwardA company studied the number of lost-time accidents occurring at its Brownsville, Texas, plant. Historical records show that 7% of the employees suffered lost- time accidents last year. Management believes that a special safety program will reduce such accidents to 5% during the current year. In addition, it estimates that 15% of employees who had lost-time accidents last year will experience a lost-time accident during the current year. a. What percentage of the employees will experience lost-time accidents in both years (to 2 decimals)? % b. What percentage of the employees will suffer at least one lost-time accident over the two-year period (to 2 decimals)? %arrow_forwardA company studied the number of lost-time accidents occurring at its Brownsville, Texas, plant. Historical records show that 9% of the employees suffered lost-time accidents last year. Management believes that a special safety program will reduce such accidents to 6% during the current year. In addition, it estimates that 15% of employees who had lost-time accidents last year will experience a lost-time accident during the current year. a. What percentage of the employees will experience lost-time accidents in both years (to 2 decimals)? % b. What percentage of the employees will suffer at least one lost-time accident over the two-year period (to 2 decimals)? %arrow_forward
- Refer to the following morbidity and mortality statistics for Community X for 2008. Total One-Year Population: 250,000 Population of Women 15-44: 75,000 Number of live births: 6,000 Total Deaths: 2,260 Number of infant deaths: 120 Deaths from heart disease: 222 Deaths from Cancer: 115 Deaths from Stroke: 90 Number of persons diagnosed with cancer 10,500 Calculate the following: Infant Mortality Rate _____________________________________ Prevalence of cancer for 2008 _____________________________ Crude Death Rate ______________________________________ Cause-specific mortality rate for stroke…arrow_forwardAssume that the national divorce rate is 30% (meaning that 30% of marriages end in divorce). In which community is the difference from this national rate statistically significant?arrow_forwardconline.austincc.edu/webapps/assessment/take/launch.jsp?course_assessment_id%3= 756751_1&course_id= 846. * Question Completion Status: QUESTION 3 An elementary school student comes down with a stomach virus the day after she swims at the local pool. Her father warns other parents at the school that the pool is unsanitary and causes virus to spread. What should the parents conclude? Choose the best answer. O The pool is indeed unsanitary and causes viruses to spread. O The pool is not unsanitary and does not cause viruses to spread. O There is an association between people visiting the pool and increased reports of viruses. O There is no association between people visiting the pool and increased reports of viruses. O Nothing can be concluded because this is an anecdote. QUESTION 4 10 Is the following an observational study or an experiment? Take a random sample of people at a fitness center. Ask them if they use resistance bands or not. Compare the average muscle mass for those who do…arrow_forward
- The top five leading causes of death in the U.S. in 2014 are shown below (Source: Health, United States, 2015, Table 19): Accidents: 136,053 Cancer: 591,699 Chronic lower respiratory disease: 147,101 Heart disease: 614,348 Stroke (cerebrovascular diseases): 133,103arrow_forwardFourteen different second-year medical students at a hospital measured the blood pressure of the same person. The systolic readings (mm Hg) are listed below. Use the given data to construct a boxplot and identify the 5-number summary.arrow_forwardThe control department of a light bulb manufacturer randomly picks 4400 light bulbs from the production lot every week. The records show that, when there is no malfunction, the defect rate in the manufacturing process ( due to imperfections in the material used) is 1%. When 1.25% or more of the light bulbs in the sample of 4400 are defective, the control unit calls repair technicians for service. Answer the following.arrow_forward
- Suppose we want to estimate the annual high temperatures of the hottest major cities in the United States. Below is data from 12 cities with the average annual temperature taken from 1971 to 2000 City Temperature (Fahrenheit) Phoenix, Arizona 87.2 Miami, Florida 84.3 Orlando, Florida 82.8 Riverside, California 80.9 Austin, Texas 79.8 Houston, Texas 79.7 San Antonio, Texas 80.3 Las Vegas, Nevada 80.1 Jacksonville, Florida 79.3 New Orleans, Louisiana 78.2 Tampa, Florida 81.7 Los Angeles, California 75.2 What's the population for this study? What's the sample for this study?arrow_forwardAccording to a climate data center, the highest temperatures (in degrees Fahrenheit) ever recorded in a certain country (as of June 15, 2017) were as follows. Present these data in a double-stem display.arrow_forwardA mining company finds that daily lost-work injuries average 1.2. If the local union contract has a clause requiring that the mine be shut down as soon as three workers incur lost-work injuries, on what percentage of the days will the mine be operational throughout the day?arrow_forward
- Discrete Mathematics and Its Applications ( 8th I...MathISBN:9781259676512Author:Kenneth H RosenPublisher:McGraw-Hill EducationMathematics for Elementary Teachers with Activiti...MathISBN:9780134392790Author:Beckmann, SybillaPublisher:PEARSON
- Thinking Mathematically (7th Edition)MathISBN:9780134683713Author:Robert F. BlitzerPublisher:PEARSONDiscrete Mathematics With ApplicationsMathISBN:9781337694193Author:EPP, Susanna S.Publisher:Cengage Learning,Pathways To Math Literacy (looseleaf)MathISBN:9781259985607Author:David Sobecki Professor, Brian A. MercerPublisher:McGraw-Hill Education